Two-layer thermal container

ABSTRACT

A two-layer thermal container according to the present invention comprises an outer container having a first intake port at an upper end thereof and an opening at a lower portion thereof; an inner container as a cylindrical body having a second intake port formed at an upper end thereof and inserted into an opening of the outer container with the outer circumferential surface of the second intake port being in close contact with the inner circumferential surface of the first intake port; a sealing member assembled to the opening to seal the opening and having its upper surface contacted with the bottom surface of the inner container; and an insertion stopper inserted into the second intake port of the inner container to seal the second intake port.

BACKGROUND OF THE INVENTION Field of the Invention

The present invention generally relates to a thermal container, and more particularly, to a thermal container having a two-layer wall that blocks direct contact with outside air.

Description of the Related Art

In order to keep the food temperature, a thermal container generally has a two-layer wall of which inner space is in a vacuum state. But, for using this conventional thermal container, the food or beverage should be cooled or heated to a desired temperature to be stored in the thermal container. Thus, especially when the beverage is intended to be stored in a cool state, the beverage should be contained in another container and then put in a refrigerator for a long time before the beverage is contained in the thermal container. Also, as time passes, the heat retaining performance may be deteriorated by air intrusion into the vacuum space between double walls of a conventional thermal container. In this case, the conventional thermal container has no means for blocking the direct heat transfer between the food and the outside air except the double wall of which the inside is initially formed to be of vacuum state Thus, when the heat retaining performance is deteriorated due to air intrusion, the conventional thermal container may come to an end of its lifespan.

Therefore, it is needed to develop a portable thermal container which blocks direct heat transfer to the outside air in addition to the double wall of which the inside is in a vacuum state and can be put with the food in it directly into a refrigerator instead of controlling the temperature of the food by putting the food in another separate container and putting it in a refrigerator before storing in the thermal container, thereby allowing it to be immediately taken out of the refrigerator.

As a prior art, ‘a manufacturing method of duplication vessel of vacuumbottle and the vessel’ was disclosed in the registered patent publication No. 10-0366670 (registered on Dec. 17, 2002). In the prior art above, an outer container 110 and an inner container 120 made of metal material are provided, an exhaust tube is formed below the outer container 110, and then the stopper connecting portion 113 at a mouth is manufactured in such a way that the stopper connecting portion 113 of the mouth is contracted than the body 111.

The stopper fastening portion 113 which has been manufactured integrally is cut at the point of the boundary between the body 111 of the outer container and the stopper connecting portion 113 at the mouth and separated from the outer container 110. Then, the stopper fastening portion 113 of the inner container is installed inside of the separated outer container 110 by overlap. And then, the stopper fastening portion 113 is rejoined to the body 111 of the outer container so as to form a vacuum room between the outer container 110 and the inner container 120. Thus, the assembly process can be simplified and various design of the outer container 110 can be allowed.

However, according to the prior art, it is hard to separate the outer container and the inner container because it is in vacuum state between them. When the outer container and the inner container are separated, forming a vacuum state will require time and efforts and extra apparatus. Thus, when the outer container and the inner container are coupled to each other, it takes a considerable time to cool the food in the inner container and put it in a refrigerator directly to drop the temperature of the food. When the food is contained in the separated inner container and is kept in a refrigerator, an extra work and apparatus will be needed to expel air from the space between the inner container and the outer container to create a vacuum in the space as rejoining the separated inner container to the outer container.

Documents of Related Art Korean Patent No. 10-0366670 (Registration date: Dec. 17, 2002)

SUMMARY OF THE INVENTION

Accordingly, the present invention has been made to resolve the problems of the prior art and to provide a two-layer thermal container which blocks direct heat transfer to the outside air and with the food contained in it can be put directly into a refrigerator and can be taken directly out of the refrigerator because there is no need to contain the food in another container to be put in a refrigerator for controlling the temperature of the food before transferring the food to the thermal container.

In order to achieve the purpose of the present invention, a two-layer thermal container includes an outer container having a first intake port at an upper end thereof and an opening at a lower portion thereof; an inner container as a cylindrical body having a second intake port formed at an upper end thereof and inserted into an opening of the outer container with the outer circumferential surface of the second intake port being in close contact with the inner circumferential surface of the first intake port; a sealing member assembled to the opening to seal the opening and having its upper surface contacted with the bottom surface of the inner container; and an insertion stopper inserted into the second intake port of the inner container to seal the second intake port.

Here, the outer container may have a two-layer wall, and preferably a vacuum state may be formed between the two layers. And preferably the sealing member may have a built-in refrigerant. Here, the sealing member may comprise an inner case and an outer case where a ventilation window is formed on the lateral surface and the bottom surface, and the lateral ventilation window and the bottom ventilation window of the outer case and the inner case can be communicated or sealed simultaneously by rotation of the inner case.

Preferably, the inner case may have a bottom surface handle which is hinge-coupled to the inner circumferential surface, in the inner circumferential surface of the bottom ventilation window of the inner case.

Preferably, the outer container has a second lateral ventilation window formed along the circumference of the lateral surface, a ventilation opening and closing cylinder is installed in the inner circumferential surface of the outer container to form a corresponding ventilation window along the circumference of the cylinder as a rotary cylinder which is in close contact with the inner circumferential surface of the outer container. A guide which rotates and supports the ventilation window opening and closing cylinder is formed in the inner circumferential surface of the outer container to be in contact with the upper and lower portions of the ventilation opening and closing cylinder thereby allowing the second lateral ventilation window and the corresponding ventilation window to be communicated with each other and sealed repeatedly by rotation of the ventilation window opening and closing cylinder.

At this time, preferably, a lateral handle may be installed in the inner circumferential surface of the corresponding ventilation window by a hinge coupling to the inner circumferential surface. Meanwhile, some portion of the lateral surface area of the outer container is cut so that the inside and the outside of the outer container are communicated with each other to form a third lateral ventilation window, a lateral surface cover is provided to close the third lateral ventilation window, a connecting arm is provided in such a way that each end of the connecting arm is hinge-coupled to one end of the lateral surface cover and the inner circumferential surface of the third lateral ventilation window respectively, and accordingly the lateral surface cover opens and closes the third lateral ventilation window by variableness of the connecting arm.

In this case, preferably, a variable plate protruded by an elastic force of an elastic body installed inside the lateral surface cover is provided on one end of the lateral surface cover, an assembly groove into which an end of the variable plate is provided in the inner circumferential surface of the third lateral ventilation window, and a switch which is integrally formed with the variable plate is provided on the surface of the lateral surface cover so as to pull back the variable plate.

By the two-layer thermal container according to the present invention, it is possible to block direct heat transfer between the food and the outside air. And also it is possible to adjust the temperature by putting directly the two-layer thermal container containing the food in a refrigerator instead of controlling the temperature of the food by putting the food in another container to be put in a refrigerator before storing in the two-layer thermal container. Thus, it is easy to carry away the thermal container from a refrigerator. And the inner container and the outer container are easy to separate and wash so that the two-layer thermal container can be in a sanitary state.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other objects, features and other advantages of the present invention will be more clearly understood from the following detailed description when taken in conjunction with the accompanying drawings, in which:

FIG. 1 is a front sectional view illustrating the prior art.

FIG. 2 is a front sectional view illustrating a basic exemplary embodiment of the present invention.

FIG. 3A is a front sectional view illustrating a first exemplary embodiment of the ventilation window of the present invention.

FIG. 3B is an exploded perspective view illustrating a first exemplary embodiment of the ventilation window of the present invention.

FIGS. 3C to 3E are bottom views illustrating a first a first exemplary embodiment of the ventilation window of the present invention.

FIG. 4 is a front sectional view illustrating an additional exemplary embodiment of the outer container according to the present invention.

FIG. 5A is a front sectional view illustrating a second exemplary embodiment of the ventilation window of the present invention.

FIG. 5B is a perspective view illustrating a second exemplary embodiment of the ventilation window of the present invention.

FIG. 5C is a perspective view illustrating a ventilation window opening and closing cylinder in a second exemplary embodiment of the ventilation window of the present invention.

FIG. 6A is a perspective view illustrating a third exemplary embodiment of the ventilation window of the present invention.

FIG. 6B is a perspective view illustrating a lateral surface cover in a third exemplary embodiment of the ventilation window of the present invention.

FIG. 6C is a front sectional view illustrating a third exemplary embodiment of the ventilation window of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Any specific structure or functional explanation that is set forth in the exemplary embodiments of the present invention is illustrated only for describing the embodiments according to the concept of the present invention. Thus, exemplary embodiments according to the concept of the present invention can be operated in various forms. And also the operable embodiments according to the present invention should not be limited to the exemplary embodiments illustrated herein. Accordingly, they should include all of appropriate all such variations, equivalents, and alternatives as fall within the scope of the present invention.

The description of the present invention comprises a basic exemplary embodiment of the present invention as illustrated in FIG. 2, a first exemplary embodiment of the ventilation window illustrated in FIGS. 3A-3E, an additional exemplary embodiment of the outer container illustrated in FIG. 4, a second exemplary embodiment of the ventilation window illustrated in FIGS. 5A-5C, and a third exemplary embodiment of the ventilation window illustrated in FIGS. 6A-6C.

Hereinafter, the embodiments of the present invention are to be described in the order described above with the accompanying drawings in detail.

<Basic Exemplary Embodiment of the Invention>

A two-layer thermal container according to a basic exemplary embodiment as illustrated in FIG. 2 comprises a outer container 10, an inner container 20 inserted into the outer container 10, an insertion stopper for sealing the inner container 20 and a sealing member 30 connected to the lower portion of the outer container 10,

The outer container 10 has an intake port provided at the top like a general beverage bottle, and the intake port herein shall be called a first intake port. An opening is formed at the bottom of the outer container 10 and a sealing member 30 seals the opening portion, thereby being connected to the outer container 10.

At this time, preferably the outer container 10 can be made of one solid wall or a multi-layer wall consisting of two or more than two walls. Then, the space between multi layers consisting of the outer container 10 may be in a vacuum state or between a vacuum state and an atmospheric pressure state. In other words, there may be some air. In this case, even though the outer container 10 consists of a multi-layer wall and there is some air between the multi layers, the inner space of the outer container 10 and the space itself between the multi layers constituting the outer container 10 act as a buffer zone. In addition, the outer container 10 as well as the inner container 20 is cooled in a refrigerator. Thereby, the air in the space between the multi layers is also cooled so as to keep the coolness of the inner container 20 which is built in the outer container 10 while carrying it for a long time.

The inner container 20 is inserted into the inside of the outer container 10 through an opening portion of the outer container 10 and is a cylindrical body which is similar to the outer container 10. Unlike the outer container 10, the bottom is closed and an intake port is formed at the top in the inner container which has a same structure as a general beverage bottle. This intake port of the inner container 20 shall be called a second intake port. And the second intake port of the inner container 20 is inserted in the first intake port of the outer container 10 such that the outer circumferential surface is tightly contacted to the inner circumferential surface of the first intake port. Thus, it can prevent outside air from entering between the first intake port and the second intake port thereby preventing pollution between the outer container 10 and the inner container 20.

The sealing member 30 is coupled to the opening portion at the bottom of the outer container 10 to seal the opening portion 10. Here, any well-known coupling means can be employed for the method for coupling the sealing member 30 to the outer container 10 and FIG. shows that the threads formed in are connected to the threads formed in the inner circumferential surface of the opening portion of the outer container 10 the outer circumferential surface of the sealing member 30. Although not shown in the drawing, a sealing material in the shape of a ring may be provided at the lower portion of the threads of the outer circumferential of the sealing member 30 for watertight sealing. In addition, a handle groove 34 in which a finger can be inserted may be formed on the bottom surface of the sealing member 30 to facilitate opening and closing the sealing member 30.

There is no limit to the inner shape of the sealing member 30, and a refrigerant may be built in the sealing member 30 to keep the temperature of the content contained in the inner container 20. Thus, the sealing member 30 can be frozen in a freezer when it is intended to keep the coolness of the content contained in the inner container 20 for a long time. The sealing member 30 can be heated separately in boiling water when it is intended to keep the warmth for a long time.

The insertion stopper 40 seals the second intake port by the method to fill the second intake port fully as illustrated in FIG. 2. Here, they may be coupled by force as illustrated in FIG. 2. Otherwise, the second intake port and the insertion stopper 40 may be coupled by a thread-coupling method.

Preferably, a mouth cover 50 may be further provided for covering all of the first intake port, the insertion stopper 40, and the second intake port. The mouth cover 50 may have threads formed in the inner circumferential surface which can be coupled to threads formed in the outer circumferential surface of the first intake port. By providing the mouth cover 50, pollution can be prevented in the insertion stopper 40 and the first intake port.

In the basic exemplary embodiment of the present invention as describe above, a direct heat transfer is prevented by the inner container 20 and the outer container 10, thereby keeping the temperature of the content contained in the inner container 20 so long that the thermal effect can last longer than using a single container to contain the content. In addition, the inner container 20 and the outer container 10 are so easy to separate and wash internally to maintain a sanitary state. When the sealing member 30 is removed, the heat of the content can be removed by putting the two-layer thermal container of the present invention itself in the refrigerator without disassembling the inner container 20 separately.

<First Exemplary Embodiment of the Ventilation Window>

As illustrated in FIG. 3A, the biggest difference between a first exemplary embodiment of the ventilation window (hereinafter called ‘first exemplary embodiment’) and the basic exemplary embodiment described above is that in the first exemplary embodiment a sealing member 30 comprises a outer case 36, an inner case 37, and a bottom circular plate 38 and all three elements above have a ventilation window, thereby enabling to cool the content at a rapid pace by communicating the ventilation windows and putting the two-layer thermal container in a refrigerator without removing the sealing member 30.

The outer case 36 constituting the sealing member 30 is formed with threads on the outer circumferential surface for engagement with the outer container 10 as in the case of the basic exemplary embodiment. However, in the first exemplary embodiment, as shown in FIG. 3B, a plurality of first lateral ventilation windows 361 are formed along the circumference of the outer case 36. At this time, preferably, the plurality of first lateral ventilation windows 361 may be formed to have the same size in positions radially symmetrical from the center of the outer case 36.

The inner case 37 is inserted into the outer case 36 and is formed in a cylindrical shape like the outer case 36. At this time, the lower portion of the outer case 36 extends in the horizontal direction toward the inner center as shown in FIG. 3A in order to prevent the inner case 37 from falling from the outer case 36. In the lateral surface of the inner case 37, a first corresponding ventilation window 371 is formed radially in the same position as the first lateral ventilation window 361 as shown in FIG. 3B. Therefore, when the inner case 37 is rotated, the first lateral ventilation window 361 and the first corresponding ventilation window 371 are communicated with each other and are staggered and sealed.

The inner case 37 is formed with a step on the bottom surface as shown in FIG. 3A. At this time, a bottom ventilation window 373 is formed on the bottom of the inner case 37, and a corresponding bottom ventilation window 383 is formed on the bottom circular plate 38.

Here, preferably, the bottom ventilation window 373 and the corresponding bottom ventilation window 383 are formed in the same position and radially in the corresponding position from the center of the bottom surface of the inner case 37 or the bottom circular plate 38. Therefore, when the bottom circular plate 38 is rotated, the bottom ventilation window 373 and the corresponding bottom ventilation window 383 are communicated with each other and sealed repeatedly. At this time, in order to prevent the bottom circular plate 38 from departing upwardly, a release prevention pin 375 may be connected to the bottom of the inner case 37 through the upper portion and lower portion of the bottom circular plate 38.

Meanwhile, the bottom circular plate 38 must be rotatable independently with respect to the inner case 37, and in order to rotate the bottom circular plate 38 a latching protrusion 382 is formed on the bottom of the bottom circular plate 38 as shown in FIG. 3A and FIG. 3C, or a bottom center handle 385 is formed in the bottom center of the bottom circular plate 38 as shown in FIG. 3D and the bottom of the inner case 37 is penetrated circularly in the center. Thus, the bottom circular plate 38 can be rotated by rotating the bottom center handle 385 with a finger or a bottom handle 387 may be installed to be hinge-coupled to the inner circumferential surface of the corresponding bottom ventilation window 383.

Therefore, the bottom ventilation window 373 and the corresponding bottom ventilation window 383 are communicated with each other by rotating the bottom circular plate 38 and the inner case 37 can be rotated by using the bottom ventilation window 373.

Thereby, when the first lateral ventilation window 361 is communicated with the first corresponding ventilation window 371, the content contained in the inner container 20 can be cooled at a rapid pace by putting the two-layer thermal container in a refrigerator and letting the cold air inside the refrigerator reach the surface of the inner container 20 even without withdrawing the inner container 20 from the two-layer thermal container.

At this time, when the outer container 10 is not a transparent container as illustrated in FIG. 3C to 3E, the first lateral ventilation window 361 and the first corresponding ventilation window 371 can be communicated with each other by aligning to match the inner ventilation marking line 362 and the outer ventilation marking line 372. The outer ventilation marking line 372 is marked on the position corresponding to the first later ventilation window 361 and the inner ventilation marking line 362 is marked on the position corresponding to the first corresponding ventilation window 371.

<Additional Exemplary Embodiment of the Outer Container>

As illustrated in FIG. 4, the difference between the additional exemplary embodiment of the outer container (hereinafter, called ‘additional exemplary embodiment’) and the basic exemplary embodiment is that while the opening portion of the outer container 10 in FIG. 2 is formed in the bottom of the outer container 10, the whole lower portion of the outer container 110 is open to form the opening portion in the additional exemplary embodiment and the sealing member 130 is formed in such a shape that the outer container 110 is extended further to the lower portion, that is, the outer container 110 and the sealing member 130 constitute the upper portion and the lower portion of one container respectively in shape.

Compared to the basic exemplary embodiment or the first exemplary embodiment, in the additional exemplary embodiment gripping to rotate the sealing member 130 is much easier, thereby making easy to separate the sealing member 130 and take out the inner container to wash. That is, when it is intended to cool the content contained in the inner container in a refrigerator, the inner container 120 and the outer container 110 in a joined state can be put in the refrigerator to be cooled at a rapid pace after removing the sealing member 130

<Second Exemplary Embodiment of the Ventilation Window>

In a second exemplary embodiment of the ventilation window (hereinafter, called ‘second exemplary embodiment’), a ventilation window is formed on the lateral surface of the outer container 210 unlike the basic exemplary embodiment or the first exemplary embodiment.

At this time, a ventilation window which is formed on the lateral surface of the outer container 210 is called a second lateral ventilation window 214. In this case, a means for closing and opening the second lateral ventilation window 214 is needed as in the first exemplary embodiment. For this, a rotary opening and closing cylinder 260 in a cylindrical shape is provided to be rotatable in close contact with the inner circumferential surface of the outer container 210 in the second exemplary embodiment, a second corresponding ventilation window 264 is formed along the lateral surface of the rotary opening and closing cylinder 260, and guides 216, 218 are protruded on the inner circumferential surface of the outer container 210 in order that the upper and lower portion of the 260 can be inserted and rotated without falling from the inner circumferential surface of the outer container 210. Here, guides 216, 218 may be formed in a circular shape to support the rotary opening and closing cylinder 260 in a cylindrical shape or formed in a shape of multiple protrusions.

In addition, a means for rotating the rotary opening and closing cylinder 260 is needed because the rotary opening and closing cylinder 260 is located inside the outer container 210. For this reason, a lateral handle 262 may be installed as being hinge-coupled to the inner circumferential surface of the second corresponding ventilation window 264 as illustrated in FIG. 5B and FIG. 5C.

<Third Exemplary Embodiment of the Ventilation Window>

In a third exemplary embodiment of the ventilation window (hereinafter, called ‘third exemplary embodiment’), a ventilation window is formed as in the first exemplary embodiment and the second exemplary embodiment, but the opening and closing of the communication window is formed in a door method unlike the first and second exemplary embodiments in which communication and sealing of the ventilation window are repeatedly formed by rotation of two cylindrical rotary bodies inside and out.

In the third exemplary embodiment, some portion of the lateral surface area of the outer container 310 is cut so that the inside and the outside of the outer container are communicated with each other to form a third lateral ventilation window 391, and a means for opening and closing the third lateral ventilation window 391 is a lateral surface cover 390 connected by a connecting arm 392 which is hinge-coupled to the inner circumferential surface of the third lateral ventilation window 391. Here, the both ends of the connecting arm 392 are hinge-coupled to the inner circumferential surface of the third lateral ventilation window 391 and the outer circumferential surface of the lateral surface cover 390 respectively, and accordingly the lateral surface cover can 390 open and close the third lateral ventilation window 391 by variableness of the connecting arm 392.

In FIG. 6A, it is shown that the connecting arm 392 is provided only in the upper portion of the lateral surface cover 390. However, the connecting arm 392 may be preferably provided equally in the upper and lower portion of the lateral surface cover 390.

In addition, a grip handle 394 for a hand-grip may be formed in a protruding shape on the lateral surface cover 390 as shown in FIG. 6A.

Meanwhile, a variable plate 396 which is inserted into the lateral surface cover 390 and protruded onto the outer circumferential surface of the lateral surface cover 390 may be provided in order to make the lateral surface cover 390 seal the third lateral ventilation window 391 firmly. Some portion of the variable plate 396 is protruded onto the outer circumferential surface of the lateral surface cover 390 and the rest is inserted into the inside of lateral surface cover 390. At this time, an elastic body 397 may be provided pushing the variable plate 396 out of the lateral surface cover 390, and an assembly groove (not illustrated) which the variable plate 396 is inserted into may be formed in the inner circumferential surface of the third ventilation window 391. In addition, a corresponding elastic body 398 having elastic force which operates in the opposite direction of elastic force of the elastic body 397 which pushes the variable plate 396 out of the lateral surface cover 390 can be provided inside the lateral surface cover 390 as shown in FIG. 6B. The corresponding elastic body 398 restrains the elastic force of the elastic body 397 to facilitate pulling back the variable plate 396 by hands.

At this time, a switch (not illustrated) which is integrally formed with the variable plate 396 and protruded to the outside of the lateral surface cover 390 may be provided.

Thereby, the inside and the outside of the outer container 310 can be communicated with each other by opening and closing the lateral surface cover 390 in the third exemplary embodiment.

In particular, in order to thoroughly seal the third lateral ventilation window 391 by the lateral surface cover 390, an airtight member 393 can be attached around the outer circumferential surface of the lateral surface cover 390 as illustrated in FIG. 6B. The airtight member 393 may be made of a stretchable material.

Although the present invention has been described in conjunction with the preferred embodiments which illustrate the technical spirit of the present invention, it will be apparent to those who are skilled in the art that the present invention is not limited only to the illustrated and described embodiments with the accompanying drawings but a lot of alternatives, variations and modifications are possible without departing from the scope of the spirit of the invention.

Although a preferred embodiment of the present invention has been described for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims. 

What is claimed is:
 1. A two-layer thermal container comprising: an outer container having a first intake port at an upper end thereof and an opening at a lower portion thereof; an inner container as a cylindrical body having a second intake port formed at an upper end thereof and inserted into an opening of the outer container with the outer circumferential surface of the second intake port being in close contact with the inner circumferential surface of the first intake port; a sealing member assembled to the opening to seal the opening and having its upper surface contacted with the bottom surface of the inner container; and an insertion stopper inserted into the second intake port of the inner container to seal the second intake port.
 2. The two-layer thermal container according to claim 1, wherein the outer container comprises a single wall or multi-layer wall, and the volume of air between each layer wall is between a vacuum state and an atmospheric pressure state when the wall is comprised of multi-layer wall.
 3. The two-layer thermal container according to claim 1, wherein the sealing member has a built-in refrigerant.
 4. The two-layer thermal container according to claim 1, wherein the sealing member includes an outer case having a first lateral ventilation window formed on a lateral surface thereof and an inner case having a first corresponding ventilation window formed on a lateral surface thereof, the first lateral ventilation window and the first corresponding ventilation window are communicated and sealed repeatedly, a bottom ventilation window is formed on the bottom of the inner case, a bottom circular plate which is freely rotatable is provided on the top surface of the bottom, and a corresponding bottom ventilation window corresponding to the bottom ventilation window is formed on the bottom circular plate to have the bottom ventilation window and the corresponding bottom ventilation window communicated and sealed repeatedly by rotation of the bottom circular plate.
 5. The two-layer thermal container according to claim 4, wherein a bottom handle is hinge-coupled to the inner circumferential surface of the corresponding bottom ventilation window of the bottom circular plate.
 6. The two-layer thermal container according to claim 1, wherein the outer container has a second lateral ventilation window formed along the circumference of the lateral surface, a rotary opening and closing cylinder having a second corresponding ventilation window formed thereon along the circumference of the cylinder is installed on the inner circumferential surface of the outer container and is in a close contact with the inner circumference of the outer container and rotatable, a guide which rotationally support the rotary opening and closing cylinder are formed on the inner circumferential surface of the outer container in such a way that the guide is in contact with the upper and lower portions of the rotary opening and closing cylinder, and the second lateral ventilation window and the second corresponding ventilation window are communicated and sealed repeatedly by rotation of the rotary opening and closing cylinder.
 7. The two-layer thermal container according to claim 6, wherein a lateral handle is installed in the inner circumferential surface of the second corresponding ventilation window by a hinge coupling to the inner circumferential surface of the second corresponding ventilation window.
 8. The two-layer thermal container according to claim 1, wherein some portion of the lateral surface area of the outer container is cut so that the inside and the outside of the outer container are communicated with each other to form a third lateral ventilation window, a lateral surface cover is provided to close the third lateral ventilation window, a connecting arm is provided in such a way that each end of the connecting arm is hinge-coupled to one end of the lateral surface cover and the inner circumferential surface of the third lateral ventilation window respectively, and accordingly the lateral surface cover opens and closes the third lateral ventilation window by variableness of the connecting arm.
 9. The two-layer thermal container according to claim 8, wherein a variable plate protruding by an elastic force of an elastic body provided inside the lateral surface cover is provided on one end of the lateral surface cover, an assembly groove into which an end of the variable plate is inserted is provided in the inner circumferential surface of the third lateral ventilation window, and a switch which is integrally formed with the variable plate is provided on the surface of the lateral surface cover so as to pull back the variable plate. 